The development of high current singly charged ion sources

Over the past 25 years many types of ion source have been developed for different applications, but here the presentation will focus on the magnetic multipole source, as it probably has the greatest physical simplicity and yet has the largest development potential. In this paper, the authors describe the underlying physics of these sources and the processes leading to the production of high currents and current densities of the required ion species including the formation of negative ions. The use of these sources is also discussed in both fusion and particle accelerator research areas, together with potential future improvements